Cigarette use and nicotine dependence are currently considered among the most pressing public health problems worldwide. Smoking is the leading cause of preventable death in the United States and the single most important avoidable cause of morbidity and premature mortality worldwide. Unlike other mental disorders (e.g., schizophrenia), the onset and chronicity of nicotine dependence could be largely prevented or diminished. It is accepted that genetic and environmental factors play a role in nicotine dependence, yet factors identified to date do not seem to completely explain this epidemic in scope or intractability. Recent evidence strongly suggests the importance of comorbid psychopathology in the onset and persistence of nicotine dependence. The overarching goal of this project is therefore to examine the relationship between anxiety disorders and depression and nicotine dependence, to examine potential mechanisms of this association, and to determine the extent to which it is generalizable to various understudied segments of the adult population. This investigation has two main Specific Aims: Aim 1: To examine the influence of anxiety disorders and depression on the onset, course, persistence, morbidity, and offset of nicotine dependence among adults in the community. Aim 2: To determine possible mechanisms of the association between anxiety disorders and depression and nicotine dependence among adults in the community (e.g., does parental psychopathology increase vulnerability to both depression and nicotine dependence). While the prevalence of cigarette smoking has declined over the past several decades, this decline has not been equal across all segments of the population and nicotine dependence has not declined as universally. Despite available information on the health risks associated with cigarette use, adults continue to initiate smoking and continue smoking, especially vulnerable segments of the population, including as females and young adults. Information gained from the proposed investigation would allow us to develop better intervention programs using existing psychiatric treatment tools aimed to reduce onset and persistence of cigarette use and nicotine dependence through both primary and secondary prevention of anxiety disorders and depression. Use of the NESARC offers a unique opportunity to analyze a large, longitudinal, epidemiologic dataset.